Post-traumatic symptoms. UCLA PTSD Reaction Index Adolescent Version (RI-R) (Rodriguez, Steinberg, & Pynoos, 1999). The RI-R is a new version of the earlier UCLA Reaction Index (Frederick, Pynoos, & Nader,1992), which was based on the DSM-III. The RI-R includes 22 items for self-report. It measures the frequency of post-traumatic symptoms in the previous four weeks. Subject are asked to note the frequency of symptoms on a scale from 0 (never) to 4 (most of the time). The measure of the severity of post-traumatic symptoms will be computed by summarizing 20 items on the questionnaire, as per Rodriguez et al (1999).